Gas-engine.



No. 854,981. PATENI'BD MAY 28, 1907.

4 w. F. BREHM.

GAS ENGINE.

APPLICATION FILED AUG. 17, 1906.

4 SHBBTS-SHEBT 1.

WITNESSES:

WITNESSES:

No. 854,981. PATENTED MAY 28, 1907 W. F. BREHM.

FIGA- FIBEI- INVENTOR No. 854,981.. PATENTED MAY 28,1907.

W. F. BREHM.

GAS ENGINE. APPLICATION IJ ILBD MIG. 17.1905.

4 SHEETS-SHEET 8.

PATENTED" MAY 2a, 1907.

W. F. 'BREHM.

GAS ENGINE. APPLIOATION rum) AUG.17.195.

4 sums-sum 4.

Fill-l2- l I G I 5 H witnesses: 6, myl m'ron UNITED sre'js P TENT- oFFIoE.

WILLIAM FREDR'ICK 'BREHM, or ROCHESTER, PENNSYLVANIA.

GAS-summer Specification of Letters Patent.

' Patented May as, 1907.

, Application filed nugnat 17,1906. ierial No 274,603

To all whom/it .mwy concern:

Be it' known that 1, WILLIAM FREDRIGK BREHM, residin atRochester, inthe county of- Beaver and tat .of Pennsylvania, a citizen of the United tates, have invented or discovered certain new and useful Improve-- ments in Gas-Engines, of whlch'lmprovements the following is a specification.

In the accompanying drawings which form a part of thisspecification Figures 1 and 2 show my improved machine in elevation and from points at right angles to one another;

3 and 4 are longitudinal Sections thereof ut on a plane which is brokenand which -is indicated by the lines III--IIIin Figs. 1

and 8, the relative positions of the moving parts in these severa figures are different as willbe, hereinafter ex lained; Figs. 5 and 6 are also views in longitudinal section of my engine and in this case also the plane ofsection is a broken one on lines indicated by the line V.V of Fig. 10, the relative 'positions'of moving iarts are again different in these two slightly different from the section upon which Figs. 5 and 6 are made, the purpose bein to, show the arrangement o ports not elsewhere adequately illustrated, the plane is indicated 'by the, line VII-VII in Big, -10;. Figs. 8, 9 and 10 are transverse'sections of the engine and the planes of these sections are also irregular and necessarily so in order to "locations of the section illustratethe arrangement of the ports; the

f indicated by the line's Vv IVIII, IX'IX and X-V III of Figs. 3 and, 4; Fig. 11 is a horizontal sectional view on the line'XIXI- of Fig. 5, as seen in the direction of the arrow a; Fig. 12 shows the piston ofthe engine, de-

tached, and Fig.- 13 is a diagrammatic view illustrating the arrangement of the ports, and it may be said to vbe a section in cylindrical path through the wall of the outer casing, and

s read upon a single plane, for purposes of i ustration. v reas which arerepeated in the several figures bear the's'ame reference numerals in each case.

The engine consists essentially of an outer casing, A, which is-c lindrical in form, an inner casing, B, whic also is cylindrical in "form and is concentrically arranged'within casing A and extends-fromon'e end of :jc'ylinrlrica bar; a lower centrally arranged chamber, 3,

7 is a view in vertical section of part only of the engine, the plane of section being again an irregular one and being lanes are however casing A part-way throughout the length thereof, and of a piston, .C, arra ed to reciprocate within casing A and provi ed with a cylindrical extension whichengages interiorly the'outer surface of inner casing B throughout the range of the pistonsreciprocating movements Cooperating with these several parts is an arrangement of the ports andpassages herein to be described, v 5

means for explodingv the gas .to impart movement to said iston, and suitable connections between sai reciprocating iston and the shaft of the engine which is riven by its re ciprocation.

Referring to the drawings piston C, as will I be seen, divides the space within the casing. A into three separate chambers, namely, an upperv chamber, 8, on one side of the piston termed the compression and explosion chamand a lower surrounding chamber, 9, these two chambers last named-being termed dislacement chambers for reasons which will hereinafter appear, one of them arranged to receive gas and the other arranged to receive air. I These two displacement chambers are, it willbe observed, on the opposite side of the piston from the compression and explosion chamber; that is, the expansive power of the contained gases tends to drive the piston in a direction opposite tothat in which the plston is driven by the expansion gases-1n the compression and explosion chamber. By-

through a port 2 in. piston G into the inner centralv displacement chamber 3, when the orifice and port, 1. and 2, are by the move-- .ment of the piston brought into an alinementone with the other. The gas. admitted may contain no air 5 or it may, and, when gas comes from a carburetor, does contam'a relativelysmall admixture of air; but in such :case the ratio] ofwaintoithe quantity-of as is so smallthat 'th e mixture is not of itse f exro plosivai; While'my invention may still be employed-though the gas be diluted with air to such an extent as to formin the displacement chamber an explosive mixture, I preferably employ gas undiluted or diluted to aslight extent. Air enters chamber 9 fromthe open atmosphere through a suitable inlet pipe, 15, the opening whereof is controlled byan outwardly'closing check-valve as isindicated in Fig. 3, and thence without other obstruction passes freely into the sur- :0 rounding displacement chamber 9.

From chamber 3 gas is caused to pass into chamber '8 through a port; 4, inpiston C (see Fig. 3) and an orifice, 5, into a passage, 6-, within casing A itself, and thence through a J port, 7, (see Fig. 5) directly into compression and explosion chamber 8. It will be understood and will hereinafter be explained that this passage of gas from ch 'amberS to chamher 8 occurs when the ports and passages are brought into alinement one with another and I this takes place in consequence of the traverse of piston C. In similar mannerau is caused to pass from the surrounding dis-' placement chamber 9 to the compression :5 and explosion chamberS through orifice 10 which is formed in the walls .of the piston, a port 11 and a passage 12 formed in the body of the outer casing A. itself, and port 1-3 directly into chamber 8 (see Fig. 7.)

osite to the ports 14 whichlead to the exaust, .This is best illustrated in Figs. 5 and.

'8. For purposes which will presently appear a bafIi-plate 18 is mounted upon piston 5 C and whentlie said several ports are opened by the stroke of'the piston, this baffle plate obstructs the direct flow from entrance to exit, and deflects such flow toward the center of the chamber. "Suitable means are employed for exploding the gas contained within chamber 8, as for example the spark-plug .19, which by an arrangement welhknown in the art ignites-the contained gas at the desired point in the operation of the machine.

5 5' It-will be observedthat my engine difiers:

from the engines which are now in usual service, first, in that the supply ofair and the suplplyof gas are kept separate up to the time w en they-are introduced into the ex= 6o plosion chamber. In consequence of this separation'itiwill be understood that explosion of the gas within the passage which leads to the ex losion chamber is-rendered' impossible an flashing-back is thereby guarded against. In the second place it 7, 13, and 14 whic cessivel will be observed that, whereas the gas-passage 6 in the wall of the outer casing through which the gas flows from chan'lber 3 to chamber 8 is formed in that portion 01 the outer casing A which extends below the lower limitsof chamber 8, passage ,]2 through which the air flows from chamber 5) into chamber 8 is formed in that portion of casing A which forms the cylindrical wall of chamber 8. This passage 12 extends substantially all the way around casing A, and

in fact constitutes an air-jacket for chamber 8. This air-jacket is in the course of the operation of the engine (presently to be described) supplied at recurring intervals with a current of air at approximately atmospheric temperature passing through it; and thus it serves to reduce thetemperature of the casing, which is heated by the successive explosions within. To further this end, S 5 ports 11 and 13, through which-the current of air passes into and out of this passage 12', are referably placed upon either side of a dividing web which is diagrammatically shown at 20 in Fig. 13 of the drawings. The 9o passing air is thus caused. to travel substantially all of the way around the casing and thereby to aflord the maximumcooling 1 eflect. c The inlet ports for the air and gas to: cham-' It remains to be ointed out that the orts 5 lilead to and from cli'am ber 8 areso arranged that, in. the descent of the piston, orts 14 are'first opened, and the openin s 0 port 13, and port 7 follow suc- The urpose here is that by 1111-400 covering the-ex aust ort first any excess pressure of the ex ibding gases within' chamber 8 will be rel eved; next, an in-ru'sh of air will follow through port 13. This inrush of air will (as I understand it) be GilGCt- 1o 5 ive to extinguish the gas which may still be burning,- and will thereby guard further against any premature/explosion. of the about to be introduced, itilClzli; will further serve to drive theproducts of the former 11c explosion from chamber- 8.. The bailieplate "18 will in this connection serve to demediatelyupon the" entrance of the air is the entrance of the gas'through port 7 the air however having been first admitted, loss of gas through the exhaust port is fore 12o stalled or prevented.- v

The operation is as follows: Beginning first with the position of the parts indicated. in Fig. ,3, piston C is at the lower extremity of its stroke In this position chamber 8 is :25 opened through ports 14 to the exhaust; and ports 5, 10, 7, and 13 are open, and gas and air are flowing through them -from chambers 3 and 9 into chamber 8. The return stroke of the piston carries it from 1 0 position illustrated in Fig. 4, the chamber -8 is reduced to relatively small volume. During this stroke also chamber 3 has increased 'in' volume to approximately double its former capacity. During this upward stroke this chamber 3 has been closed and consequently the gas which it contains has been correspondingly reduced in density -or rarefied. At the same time chamber 9, being in open communication with the outer air through port15, continues to take in air in consequence of .the' displacement caused by piston C; and when the pistonreaches the upper limit of its stroke, this chamber 9 contains air at approximately atmospheric pressure. When however the piston reaches this .position, port 2 comes into alinement with orifice land gas flows,

into chamber 3 until the normal density of the gas is restored and gas pressure within the chamber is approximately that of the supply. (It will be understood that the pressure of the gas supply may be-such as is found most desirable.) When the piston reaches this upward limit of its stroke the explosion occurs; and the mingled gas and air which the chamber S contains is ignited or exploded, and the force of that explosion drives the piston from the position in which it then is, through an entire'traverse which is a downward and a return stroke. The piston passing downward first cuts off communication between port 2 and orifice 1 and at the same time closes the check-valve in the air supply pipe. Thereafter through: out the downward traverse of the piston,

the gas contained in chamber 3 and the air contained in chamber 9 are compressed with a correspondingly increased density. When the pistonapproaches the lower limit of its traverse as is-indicated in Figs. 3, 5 and 7 the exhaustports 14 are uncovered causing a flow of the products of combustion-from the chamber 8 to the exhaust 17; and gas and" air flow throughtherout'e indicated by 4, 5, 6, and 7 and the route indicated by 10, 11, 12, and 13 from chambers 3 and 9 re-v spectively into chamber 8. This flow. is

"consequent upon the compression of the displacement takes place from chambers 3- I and 9 into chamber 8 consequent upon a compression due to the traverse of the piston. Chamber 8 being then filled again with the mixture of air and gas, the piston again rises to compress the'mingled gas and air in chamber 8, and therein the operation is renewed. a

The emptying of the roducts of explosion froinchamber 8 when t ie piston reaches the lower limit of its traverse has been noted above. It remains only to observe that when the piston is in the position shown'in' Fig. 3, that is'atthe downward limit of its movement, chamber 3fcontains a quantity of gas sufficient under the pressure of the gas supply to fill this chamber when atits maximum capacity. That is at its capa'city when the piston is in the position shown in Fig. 4.

At the same time chamber 9 contains air which has been com v ressed by the descent of the piston. It is t e.expansion of. the gas and air confined in these chambers 3 and 9 which causes chamber 8 to be filled with the new-and unburned mixture of air and gas.

Itwill be understood that by proper proportion of parts the amount of this displacement in consequence of compression may be varied,

and the amount of gas and air delivered into chamber 8 may be thus controlled; thus the amount found most desirable for thoroughly emptying chamber 8 and at the same time refilling it with unburned gas and air may be employed. I claim herein as my invention:

. 1. In a gas engine the conibinationof a reciprocating iston, a chamber for compression and exp osion arranged upon one side of said piston, displacement chambers for gas and air respectively arranged upon the'opposite side of said piston, and communications controlled by such movement of said piston, for admitting air and gas to said displacement chambers, for, permitting the air :and'

gas to pass from said displacement chambers to said chamber for compression and explosion and for discharging the products of ex ,plosion' from the last named chamber, substantially as described.

2. In a gas engine, the combination of an outer cylinder, a piston reciprocating therein and dividing the space within said outer cylinder into a, chamber for compressi'onand explosion and a space for receiving air and gas, an inner cylinder arranged within said outer cylinder and at one side of said piston and cooperating with said piston to divide the space for receiving air and gas into separate dis placement-chambers, a gas inlet, an air inlet, an exhaust, means for causing explosion of gas in said chamber for compression and ex: plosion and several means operative on the traverse of the piston for admitting air and gas to the displacement chambers, forcaus- IVIS ing air and gas to pass from said displacew &

' sion and explosion and-from the last named chamber to the exhaust, substantially asdeand dividing the space within said cylinder v3 a chamber for compression and explosionv closed by a movable piston, an arrangement of ports in said chamber such that air and gas enter said chamber unmingled at one side thereof and the products of explosion pass from saidchamberat the opposite side thereof, and a baffle plate arranged to obstruct direct passage ofgas and air from inlet to exhaust; when both inlet and .exhaustv ports are open, substantially as described.

5. In a gas engine the combination of a cylinder of uniform diameter from end to end,.a piston reciprocating in said cylinder into a chamber for compression and explosion, and a space for receiving. air and gas,jan

inner cylinder arranged within said outer cylinder and at one side of said piston and co-operating with said piston to divide the space for receiving air and gas into separate displacement chambers, and communications controlled by said piston in its movement for admitting air and gas to said displacement chambers for permitting air and gas to pass from said displacement chambers to said chamber for compression and explosion, and for discharging'the products of explosion from the last named chamber, substantially as described' 6. In a gas engine the combination of a cylinder and a piston. reciprocating therein, separate chambers for gas and air on one side of said piston. wherein gas and air are compressed by traverse of said piston in one direction and wherein gas and air are admitted on traverse of the piston in opposite direction, and an explosion chamber on the opposite side of said piston to which gas and air are admitted from said gas and air chambers and in which gas and air so admitted are exploded to drive said-piston,, substantially as described.

7. In a gas engine the combination of an outer cylinder, an inner cylinder concentrically arranged therein and extending from one end of the outer cylinder part way of the length thereof, a piston arranged within the outer cylinder and. by a cylindrical extension bearing also upon the outer surface of the inner cylinder, and dividing the space within said outer casing into a compression and ex plosion chamber at one side thereof and central and peripheral chambers for gas and air at the other side thereof, and reciprocating to vary the volumes of said several chambers, an air supply leading to said air chamber and controlled by an inwardly closing checkvalve, a gas supply leading to said gas chamher and a port for admitting gas irom'said supply to said chamber opened when the volume of said chamber is at its maximum, ports for admitting air and gas from said air and gas chambers to said compression and explosion chamberwhen the volumes of said gas, and air chambers are at their minimum, a port opening from said compression and explosion chamber to an exhaust when the volume of' said explosion and compression chamber is atits maximum, and. means for exploding the gas within said explosion and compression chamber when the volume of said chamber 18 at its minimum, substan tially as described.

In testimony whereof, I have hereunto set my hand.

WILLIAM FREDRICK BREllM. Witnesses:

BAYARD H. OHRIsTY, HERBERT BRADLEY. 

